The Curse of Naxxramas first wing is actually free for a limited time which is why the servers are being whacked. In this update players will take on “a series of iconic, necrotic bosses, each with its own unique powers and cards to command”. There are 30 new cards being added in this update which can be collected and used in normal games.

Each week a new wing will open for the sum of 700 gold per wing or $6.99 per wing. Bundles are also available with four wings costing $19.99, three wings for $14.99, and two wings are bundled at $9.99.